Lower alkyl esters of n-alkoxyalkylthiolcarbamic acids



Unite States Patent LOWER ALKYL ESTERS 0F N-ALKOXY- ALKYLTHIOLARBAMIC ACIDS Harry Tilles, El Cerrito, and Joe Antognini, Mountain View, Calif., assignors to Staulfer Chemical Company, a corporation of Delaware No Drawing. Application February 13, 1957 Serial No. 639,854

6 Claims. (Cl. 260-455) This invention relates to certain novel lower alkyl esters of N alkoxyalkylthiolcarbarnic acids as compositions of matter and as herbicides. More specifically, the

invention relates to compounds of the general formula The novel compounds of the present invention may be made in accordance with the following non-limiting examples. Code numbers have been assigned to each compound and are used throughout the balance of the application.

Example 1-(R-2048).-10 g. (0.072 mol) of n-propyl chlorothiolformate was dissolved in 125 cc. of ethyl ether and the solution was cooled to 10 C. in an ice bath. 13.2 g. (0.148 mole) of B-methoxypropylamine was slowly added, keeping the reaction mixture cool by means of the ice bath. The reaction mixture was then filtered from the solid amine hydrochloride and the ether filtrate was concentrated on a steam bath with the aid of a current of air. The residual liquid was then fractionated through an 18" Podbielniak Heli-Grid fractional distillation column. There was obtained 8.0 g. of npropyl N-3-methoxypropylthiolcarbamate, B.P. (5.0 mm.) 143144 C., 12 1.4847.

Example 2(R-2089).When the general procedure of Example 1 was repeated except that 14.7 g. (0.165 mole) of S-methoxypropylamine and g. (0.080 mole) of ethyl chlorothiolformate were employed, there was obtained 13.5 g. of undistilled ethyl N-S-methoxypropylthiolcarbamate, 11 1.4869.

Example 3(R-2091).When the general procedure of Example lwas repeated except that 11.9 g. (0.134 mole) of S-methoxypropylamine and 10 g. (0.066 mole) of n-butyl chlorothiolformate were employed, there was obtained 13.3 g. of undistilled n-butyl N-3-methoxypropylthiolcarbamate, n 1.4840.

Example 4--(R-2092).-19 g. (0.165 mole) of 65% beta-methoxyethylamine was added to 125 cc. of ethyl ether and the mixture was cooled to 5-10 C. in an ice bath. 10 g. (0.080 mole) of ethyl chlorothiolformate was slowly added, keeping the reaction mixture cool by means of the ice bath. The ether phase was then separated fiom the water layer, dried over anhydrous magnesium sulfate and the ether was evaporated, first on a steam bath and finally under water pump vacuum with the aid of a Rinco Rotating Evaporator. There was obtained as a residue, 12 g. of ethyl beta-methoxyethylthiolcarbamate, 11 1.4857.

Example 5(R2093).When the general procedure of Example 4 was repeated except that 17.7 g. (0.153 mole) of 65% beta-methoxyethylamine and 10.3 g. (0.075 mole) of n-propyl chlorothiolformate were employed, there was obtained 12 g. of n-propyl beta-methoxyethylthiolcarbamate, n 1.4841.

The compounds of the present invention have been tested as herbicides and found very effective as the following typical tests show. Some of the compounds are quite selective in their action and can be used to eradicate or control one type of plant, while another type of plant is relatively unaffected.

In making the following tests, seeds were planted in 3" pots and shortly thereafter the compound under test was applied to the pots as a drench at the rate of 365 pounds per acre. The pots were placed in a greenhouse and watered at suitable intervals and the germination and growth of the seeds was compared with similarly planted seeds to which no herbicide was added. In each case, germination was reported on the scale of 0-100%, while growth was reported on a scale of 0-10, based on the seeds which germinated. Thus, -10 indicates normal germination and normal growth.

The following data were obtained:

Oats Cucumber Radish O ompound Percent Growth Percent Growth Percent Growth Germ. Germ. Germ.

wherein R is a lower alkyl group and R is a lower alkoxyalkyl group.

2. The chemical compound ethyl N-methoxypropyl thiolcarbamate.

3. The chemical compound n-propyl N-methoxypropyl thiolcarbamate.

4. The chemical compound n-butyl N-methoxypropyl thiolcarbamate.

5. The chemical compound ethyl N-methoxyethyl thiolcarbamate.

6. The chemical compound n-propyl N-methoxyethyl thiolcarbamate.

References Cited in the file of this patent UNITED STATES PATENTS 2,160,880 Loane et a1. June 6, 1939 2,562,011 Baumgartner July 24, 1951 2,608,575 Mathes Aug. 26, 1952 7 2,631,935 Baumgartner Mar. 17, 1953 2,642,451 Weijlard et a1 June 16, 1953 2,687,348 Kosmin Aug. 24, 1954 2,786,866 Hook et a1. Mar. 26, 1957 

1. THE CHEMICAL COMPOUND: 